package com.qms.repast.weidgets;

import android.content.Context;
import android.content.res.TypedArray;
import android.graphics.Canvas;
import android.graphics.Rect;
import android.graphics.drawable.Drawable;
import android.support.v7.widget.LinearLayoutManager;
import android.support.v7.widget.RecyclerView;
import android.view.View;

/**
 * @author 泅渡者
 * @date 2018/7/16 0016
 * @describe:
 */
public class MyDecoration extends RecyclerView.ItemDecoration {

	private Context mContext;
	private Drawable mDivider;
	private int mOrientation;
	public static final int HORIZONTAL_LIST = LinearLayoutManager.HORIZONTAL;
	public static final int VERTICAL_LIST = LinearLayoutManager.VERTICAL;
	/**
	 * 我们通过获取系统属性中的listDivider来添加，在系统中的AppTheme中设置
	 */
	public static final int[] ATRRS = new int[]{
			android.R.attr.listDivider
	};

	public MyDecoration (Context context, int orientation) {
		this.mContext = context;
		final TypedArray ta = context.obtainStyledAttributes(ATRRS);
		this.mDivider = ta.getDrawable(0);
		ta.recycle();
		setOrientation(orientation);
	}

	public MyDecoration (Context context, int orientation, int resId) {
		this.mContext = context;
		this.mDivider = this.mContext.getDrawable(resId);
		setOrientation(orientation);
	}

	/**
	 * 设置屏幕的方向
	 *
	 * @param orientation
	 */
	public void setOrientation (int orientation) {
		if (orientation != HORIZONTAL_LIST && orientation != VERTICAL_LIST) {
			throw new IllegalArgumentException("invalid orientation");
		}
		mOrientation = orientation;
	}

	@Override
	public void onDraw (Canvas c, RecyclerView parent, RecyclerView.State state) {
		if (mOrientation == HORIZONTAL_LIST) {
			drawVerticalLine(c, parent, state);
		} else {
			drawHorizontalLine(c, parent, state);
		}
	}

	/**
	 * 画横线, 这里的parent其实是显示在屏幕显示的这部分
	 *
	 * @param c
	 * @param parent
	 * @param state
	 */
	public void drawHorizontalLine (Canvas c, RecyclerView parent, RecyclerView.State state) {
		int left = parent.getPaddingLeft();
		int right = parent.getWidth() - parent.getPaddingRight();
		final int childCount = parent.getChildCount();
		for (int i = 0; i < childCount; i++) {
			final View child = parent.getChildAt(i);

			//获得child的布局信息
			final RecyclerView.LayoutParams params = (RecyclerView.LayoutParams) child.getLayoutParams();
			final int top = child.getBottom() + params.bottomMargin;
			final int bottom = top + mDivider.getIntrinsicHeight();
			mDivider.setBounds(left, top, right, bottom);
			mDivider.draw(c);
			//Log.d("wnw", left + " " + top + " "+right+"   "+bottom+" "+i);
		}
	}

	/**
	 * 画竖线
	 *
	 * @param c
	 * @param parent
	 * @param state
	 */
	public void drawVerticalLine (Canvas c, RecyclerView parent, RecyclerView.State state) {
		int top = parent.getPaddingTop();
		int bottom = parent.getHeight() - parent.getPaddingBottom();
		final int childCount = parent.getChildCount();
		for (int i = 0; i < childCount; i++) {
			final View child = parent.getChildAt(i);

			//获得child的布局信息
			final RecyclerView.LayoutParams params = (RecyclerView.LayoutParams) child.getLayoutParams();
			final int left = child.getRight() + params.rightMargin;
			final int right = left + mDivider.getIntrinsicWidth();
			mDivider.setBounds(left, top, right, bottom);
			mDivider.draw(c);
		}
	}

	/**
	 * 由于Divider也有长宽高，每一个Item需要向下或者向右偏移
	 *
	 * @param outRect
	 * @param view
	 * @param parent
	 * @param state
	 */
	@Override
	public void getItemOffsets (Rect outRect, View view, RecyclerView parent, RecyclerView.State state) {
		if (mOrientation == HORIZONTAL_LIST) {
			//画横线，就是往下偏移一个分割线的高度
			outRect.set(0, 0, mDivider.getIntrinsicWidth(), 0);

		} else {
			//画竖线，就是往右偏移一个分割线的宽度
			outRect.set(0, 0, 0, mDivider.getIntrinsicHeight());

		}
	}
}


